For a one-way clutch it is known to use wedge plates, forming a cone-shaped outer circumferential surface disposed within a groove for an outer race, to rotationally connect the outer race with an inner race. To enable a consistent transition from a free-wheel mode to a locking mode, it is necessary to maintain some frictional contact between the cone-shaped outer circumferential surface and the groove during the free-wheel mode. The frictional contact results in torque drag between the inner and outer races and subsequent energy dissipation and decrease in efficiency during operation in free-wheel mode.
FIG. 8 is a partial cross-sectional view of a prior art one-way clutch. FIG. 8 is taken from FIG. 10 of U.S. Pat. No. 3,202,250. FIG. 8 shows split outer race 36 for a one-way clutch. The two portions of race 36 are axially fixed by screw 37. The one-way clutch described in U.S. Pat. No. 3,202,250 operates with drag torque between wedge elements, radially located between inner and outer races, during free-wheel mode.